Why you should care

How many representatives in Congress embroiled in the immigration debate do you think take public transit to work?

Probably not that many. But if they were, it just might change the way they vote. Because a new Harvard study polled Massachusetts commuters — mostly white residents from towns with very small Hispanic-American populations (less than 6 percent) — and found that after just three days of riding public transit, they were a little more hostile to immigrants.

But 10 days is all it takes to make you “less exclusionary,” as the researchers put it.

How did the study go down? It yielded minor changes, to be fair, but researchers recruited Hispanic men from Craigslist, as the the lead author told the Boston Globe — all in an effort to slowly expose the mostly white (85 percent of the commuters in the study self-identified that way) commuters to the subject of the immigration debate. (See the Globe’s graphic on the study for an illustration.) Commuters were asked questions that are flashpoints in immigration policy — e.g., ”Should English be the official language?” “Should children of undocumented immigrants be allowed to stay?” — and their answers were (marginally) harsher after three days, but friendlier after 10.

Of course, the fact that the whole thing was orchestrated raises its own set of questions. And while the thesis is a nice one — that encountering new types of people (and faces) could gradually change your attitude toward them over time (if you see them consistently for longer than three days) – we remain skeptical. Because that kind of melting pot, as we know, doesn’t happen so naturally on most transit lines, which have remained stubbornly segregated, or used by one or two racial groups much more than others. That’s been the case in cities like Atlanta — or, to take it globally, Jerusalem. (New York does better on this scale, but, still.)

You don’t need Rosa Parks or a Harvard study to tell you that public transportation has deep racial hues to it. And while most Americans still drive solo rather than taking public transport, 84 percent of white Americans compared to less than 70 percent of Hispanic Americans commute. That’s a big gap, pointing to the reality that even if the subway lines could integrate us a bit better, well, you kind of need everyone to be using the subway lines in equal measure.

Just 5 percent of Americans use public transportation as their main form of commuting. But there’s something to think about here — for the immigration debate and for the $302 billion bill Obama’s just proposed to pump up transportation (including infrastructure and public transit).